cakephp2-php8/cake/libs/cake_session.php
2011-02-05 01:29:35 -05:00

752 lines
18 KiB
PHP

<?php
/**
* Session class for Cake.
*
* Cake abstracts the handling of sessions.
* There are several convenient methods to access session information.
* This class is the implementation of those methods.
* They are mostly used by the Session Component.
*
* PHP 5
*
* CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
* Copyright 2005-2010, Cake Software Foundation, Inc. (http://cakefoundation.org)
*
* Licensed under The MIT License
* Redistributions of files must retain the above copyright notice.
*
* @copyright Copyright 2005-2010, Cake Software Foundation, Inc. (http://cakefoundation.org)
* @link http://cakephp.org CakePHP(tm) Project
* @package cake.libs
* @since CakePHP(tm) v .0.10.0.1222
* @license MIT License (http://www.opensource.org/licenses/mit-license.php)
*/
if (!class_exists('Security')) {
App::import('Core', 'Security');
}
/**
* Session class for Cake.
*
* Cake abstracts the handling of sessions. There are several convenient methods to access session information.
* This class is the implementation of those methods. They are mostly used by the Session Component.
*
* @package cake.libs
*/
class CakeSession {
/**
* True if the Session is still valid
*
* @var boolean
*/
public static $valid = false;
/**
* Error messages for this session
*
* @var array
*/
public static $error = false;
/**
* User agent string
*
* @var string
*/
protected static $_userAgent = '';
/**
* Path to where the session is active.
*
* @var string
*/
public static $path = '/';
/**
* Error number of last occurred error
*
* @var integer
*/
public static $lastError = null;
/**
* 'Security.level' setting, "high", "medium", or "low".
*
* @var string
*/
public static $security = null;
/**
* Start time for this session.
*
* @var integer
*/
public static $time = false;
/**
* Cookie lifetime
*
* @var integer
*/
public static $cookieLifeTime;
/**
* Time when this session becomes invalid.
*
* @var integer
*/
public static $sessionTime = false;
/**
* Current Session id
*
* @var string
*/
public static $id = null;
/**
* Hostname
*
* @var string
*/
public static $host = null;
/**
* Session timeout multiplier factor
*
* @var integer
*/
public static $timeout = null;
/**
* Number of requests that can occur during a session time without the session being renewed.
* This feature is only used when `Session.harden` is set to true.
*
* @var integer
* @see CakeSession::_checkValid()
*/
public static $requestCountdown = 10;
/**
* Constructor.
*
* @param string $base The base path for the Session
* @param boolean $start Should session be started right now
*/
public static function init($base = null, $start = true) {
self::$time = time();
$checkAgent = Configure::read('Session.checkAgent');
if (($checkAgent === true || $checkAgent === null) && env('HTTP_USER_AGENT') != null) {
self::$_userAgent = md5(env('HTTP_USER_AGENT') . Configure::read('Security.salt'));
}
self::_setPath($base);
self::_setHost(env('HTTP_HOST'));
}
/**
* Setup the Path variable
*
* @param string $base base path
* @return void
*/
protected static function _setPath($base = null) {
if (empty($base)) {
self::$path = '/';
return;
}
if (strpos($base, 'index.php') !== false) {
$base = str_replace('index.php', '', $base);
}
if (strpos($base, '?') !== false) {
$base = str_replace('?', '', $base);
}
self::$path = $base;
}
/**
* Set the host name
*
* @param string $host Hostname
* @return void
*/
protected static function _setHost($host) {
self::$host = $host;
if (strpos(self::$host, ':') !== false) {
self::$host = substr(self::$host, 0, strpos(self::$host, ':'));
}
}
/**
* Starts the Session.
*
* @return boolean True if session was started
*/
public static function start() {
if (self::started()) {
return true;
}
$id = self::id();
session_write_close();
self::_configureSession();
self::_startSession();
if (!$id && self::started()) {
self::_checkValid();
}
self::$error = false;
return self::started();
}
/**
* Determine if Session has been started.
*
* @return boolean True if session has been started.
*/
public static function started() {
return isset($_SESSION) && session_id();
}
/**
* Returns true if given variable is set in session.
*
* @param string $name Variable name to check for
* @return boolean True if variable is there
*/
public static function check($name = null) {
if (!self::started() && !self::start()) {
return false;
}
if (empty($name)) {
return false;
}
$result = Set::classicExtract($_SESSION, $name);
return isset($result);
}
/**
* Returns the Session id
*
* @param id $name string
* @return string Session id
*/
public static function id($id = null) {
if ($id) {
self::$id = $id;
session_id(self::$id);
}
if (self::started()) {
return session_id();
}
return self::$id;
}
/**
* Removes a variable from session.
*
* @param string $name Session variable to remove
* @return boolean Success
*/
public static function delete($name) {
if (self::check($name)) {
self::__overwrite($_SESSION, Set::remove($_SESSION, $name));
return (self::check($name) == false);
}
self::__setError(2, __("%s doesn't exist", $name));
return false;
}
/**
* Used to write new data to _SESSION, since PHP doesn't like us setting the _SESSION var itself
*
* @param array $old Set of old variables => values
* @param array $new New set of variable => value
* @access private
*/
private static function __overwrite(&$old, $new) {
if (!empty($old)) {
foreach ($old as $key => $var) {
if (!isset($new[$key])) {
unset($old[$key]);
}
}
}
foreach ($new as $key => $var) {
$old[$key] = $var;
}
}
/**
* Return error description for given error number.
*
* @param integer $errorNumber Error to set
* @return string Error as string
* @access private
*/
private static function __error($errorNumber) {
if (!is_array(self::$error) || !array_key_exists($errorNumber, self::$error)) {
return false;
} else {
return self::$error[$errorNumber];
}
}
/**
* Returns last occurred error as a string, if any.
*
* @return mixed Error description as a string, or false.
*/
public static function error() {
if (self::$lastError) {
return self::__error(self::$lastError);
}
return false;
}
/**
* Returns true if session is valid.
*
* @return boolean Success
*/
public static function valid() {
if (self::read('Config')) {
if (self::_validAgentAndTime() && self::$error === false) {
self::$valid = true;
} else {
self::$valid = false;
self::__setError(1, 'Session Highjacking Attempted !!!');
}
}
return self::$valid;
}
/**
* Tests that the user agent is valid and that the session hasn't 'timed out'.
* Since timeouts are implemented in CakeSession it checks the current self::$time
* against the time the session is set to expire. The User agent is only checked
* if Session.checkAgent == true.
*
* @return boolean
*/
protected static function _validAgentAndTime() {
$validAgent = (
Configure::read('Session.checkAgent') === false ||
self::$_userAgent == self::read('Config.userAgent')
);
return ($validAgent && self::$time <= self::read('Config.time'));
}
/**
* Get / Set the userAgent
*
* @param string $userAgent Set the userAgent
* @return void
*/
public static function userAgent($userAgent = null) {
if ($userAgent) {
self::$_userAgent = $userAgent;
}
return self::$_userAgent;
}
/**
* Returns given session variable, or all of them, if no parameters given.
*
* @param mixed $name The name of the session variable (or a path as sent to Set.extract)
* @return mixed The value of the session variable
*/
public static function read($name = null) {
if (!self::started() && !self::start()) {
return false;
}
if (is_null($name)) {
return self::__returnSessionVars();
}
if (empty($name)) {
return false;
}
$result = Set::classicExtract($_SESSION, $name);
if (!is_null($result)) {
return $result;
}
self::__setError(2, "$name doesn't exist");
return null;
}
/**
* Returns all session variables.
*
* @return mixed Full $_SESSION array, or false on error.
*/
private static function __returnSessionVars() {
if (!empty($_SESSION)) {
return $_SESSION;
}
self::__setError(2, 'No Session vars set');
return false;
}
/**
* Writes value to given session variable name.
*
* @param mixed $name Name of variable
* @param string $value Value to write
* @return boolean True if the write was successful, false if the write failed
*/
public static function write($name, $value = null) {
if (!self::started() && !self::start()) {
return false;
}
if (empty($name)) {
return false;
}
$write = $name;
if (!is_array($name)) {
$write = array($name => $value);
}
foreach ($write as $key => $val) {
self::__overwrite($_SESSION, Set::insert($_SESSION, $key, $val));
if (Set::classicExtract($_SESSION, $key) !== $val) {
return false;
}
}
return true;
}
/**
* Helper method to destroy invalid sessions.
*
* @return void
*/
public static function destroy() {
if (self::started()) {
session_destroy();
}
self::clear();
}
/**
* Clears the session, the session id, and renew's the session.
*
* @return void
*/
public static function clear() {
$_SESSION = null;
self::$id = null;
self::start();
self::renew();
}
/**
* Helper method to initialize a session, based on Cake core settings.
*
* Sessions can be configured with a few shortcut names as well as have any number of ini settings declared.
*
* @return void
* @throws CakeSessionException Throws exceptions when ini_set() fails.
*/
protected static function _configureSession() {
$sessionConfig = Configure::read('Session');
$iniSet = function_exists('ini_set');
if (isset($sessionConfig['defaults'])) {
$defaults = self::_defaultConfig($sessionConfig['defaults']);
if ($defaults) {
$sessionConfig = Set::merge($defaults, $sessionConfig);
}
}
if (!isset($sessionConfig['ini']['session.cookie_secure']) && env('HTTPS')) {
$sessionConfig['ini']['session.cookie_secure'] = 1;
}
if (isset($sessionConfig['timeout']) && !isset($sessionConfig['cookieTimeout'])) {
$sessionConfig['cookieTimeout'] = $sessionConfig['timeout'];
}
if (!isset($sessionConfig['ini']['session.cookie_lifetime'])) {
$sessionConfig['ini']['session.cookie_lifetime'] = $sessionConfig['cookieTimeout'] * 60;
}
if (!isset($sessionConfig['ini']['session.name'])) {
$sessionConfig['ini']['session.name'] = $sessionConfig['cookie'];
}
if (!empty($sessionConfig['handler'])) {
$sessionConfig['ini']['session.save_handler'] = 'user';
}
if (empty($_SESSION)) {
if (!empty($sessionConfig['ini']) && is_array($sessionConfig['ini'])) {
foreach ($sessionConfig['ini'] as $setting => $value) {
if (ini_set($setting, $value) === false) {
throw new CakeSessionException(sprintf(
__('Unable to configure the session, setting %s failed.'),
$setting
));
}
}
}
}
if (!empty($sessionConfig['handler']) && !isset($sessionConfig['handler']['engine'])) {
call_user_func_array('session_set_save_handler', $sessionConfig['handler']);
}
if (!empty($sessionConfig['handler']['engine'])) {
$handler = self::_getHandler($sessionConfig['handler']['engine']);
session_set_save_handler(
array($handler, 'open'),
array($handler, 'close'),
array($handler, 'read'),
array($handler, 'write'),
array($handler, 'destroy'),
array($handler, 'gc')
);
}
Configure::write('Session', $sessionConfig);
self::$sessionTime = self::$time + ($sessionConfig['timeout'] * 60);
}
/**
* Find the handler class and make sure it implements the correct interface.
*
* @return void
*/
protected static function _getHandler($handler) {
list($plugin, $class) = pluginSplit($handler, true);
$found = App::import('Lib', $plugin . 'session/' . $class);
if (!$found) {
App::import('Core', 'session/' . $class);
}
if (!class_exists($class)) {
throw new CakeSessionException(__('Could not load %s to handle the session.', $class));
}
$handler = new $class();
if ($handler instanceof CakeSessionHandlerInterface) {
return $handler;
}
throw new CakeSessionException(__('Chosen SessionHandler does not implement CakeSessionHandlerInterface it cannot be used with an engine key.'));
}
/**
* Get one of the prebaked default session configurations.
*
* @return void
*/
protected static function _defaultConfig($name) {
$defaults = array(
'php' => array(
'cookie' => 'CAKEPHP',
'timeout' => 240,
'cookieTimeout' => 240,
'ini' => array(
'session.use_trans_sid' => 0,
'session.cookie_path' => self::$path,
'session.save_handler' => 'files'
)
),
'cake' => array(
'cookie' => 'CAKEPHP',
'timeout' => 240,
'cookieTimeout' => 240,
'ini' => array(
'session.use_trans_sid' => 0,
'url_rewriter.tags' => '',
'session.serialize_handler' => 'php',
'session.use_cookies' => 1,
'session.cookie_path' => self::$path,
'session.auto_start' => 0,
'session.save_path' => TMP . 'sessions',
'session.save_handler' => 'files'
)
),
'cache' => array(
'cookie' => 'CAKEPHP',
'timeout' => 240,
'cookieTimeout' => 240,
'ini' => array(
'session.use_trans_sid' => 0,
'url_rewriter.tags' => '',
'session.auto_start' => 0,
'session.use_cookies' => 1,
'session.cookie_path' => self::$path,
'session.save_handler' => 'user',
),
'handler' => array(
'engine' => 'CacheSession',
'config' => 'default'
)
),
'database' => array(
'cookie' => 'CAKEPHP',
'timeout' => 240,
'cookieTimeout' => 240,
'ini' => array(
'session.use_trans_sid' => 0,
'url_rewriter.tags' => '',
'session.auto_start' => 0,
'session.use_cookies' => 1,
'session.cookie_path' => self::$path,
'session.save_handler' => 'user',
'session.serialize_handler' => 'php',
),
'handler' => array(
'engine' => 'DatabaseSession',
'model' => 'Session'
)
)
);
if (isset($defaults[$name])) {
return $defaults[$name];
}
return false;
}
/**
* Helper method to start a session
*
* @return boolean Success
*/
protected static function _startSession() {
if (headers_sent()) {
if (empty($_SESSION)) {
$_SESSION = array();
}
} elseif (!isset($_SESSION)) {
session_cache_limiter ("must-revalidate");
session_start();
header ('P3P: CP="NOI ADM DEV PSAi COM NAV OUR OTRo STP IND DEM"');
} else {
session_start();
}
return true;
}
/**
* Helper method to create a new session.
*
* @return void
*/
protected static function _checkValid() {
if (!self::started() && !self::start()) {
self::$valid = false;
return false;
}
if (self::read('Config')) {
$sessionConfig = Configure::read('Session');
if (self::_validAgentAndTime()) {
$time = self::read('Config.time');
self::write('Config.time', self::$sessionTime);
if (isset($sessionConfig['autoRegenerate']) && $sessionConfig['autoRegenerate'] === true) {
$check = self::read('Config.countdown');
$check -= 1;
self::write('Config.countdown', $check);
if (time() > ($time - ($sessionConfig['timeout'] * 60) + 2) || $check < 1) {
self::renew();
self::write('Config.countdown', self::$requestCountdown);
}
}
self::$valid = true;
} else {
self::destroy();
self::$valid = false;
self::__setError(1, 'Session Highjacking Attempted !!!');
}
} else {
self::write('Config.userAgent', self::$_userAgent);
self::write('Config.time', self::$sessionTime);
self::write('Config.countdown', self::$requestCountdown);
self::$valid = true;
}
}
/**
* Restarts this session.
*
* @return void
*/
public static function renew() {
if (session_id()) {
if (session_id() != '' || isset($_COOKIE[session_name()])) {
setcookie(Configure::read('Session.cookie'), '', time() - 42000, self::$path);
}
session_regenerate_id(true);
}
}
/**
* Helper method to set an internal error message.
*
* @param integer $errorNumber Number of the error
* @param string $errorMessage Description of the error
* @return void
* @access private
*/
private static function __setError($errorNumber, $errorMessage) {
if (self::$error === false) {
self::$error = array();
}
self::$error[$errorNumber] = $errorMessage;
self::$lastError = $errorNumber;
}
}
/**
* Interface for Session handlers. Custom session handler classes should implement
* this interface as it allows CakeSession know how to map methods to session_set_save_handler()
*
* @package cake.libs
*/
interface CakeSessionHandlerInterface {
/**
* Method called on open of a session.
*
* @return boolean Success
*/
public function open();
/**
* Method called on close of a session.
*
* @return boolean Success
*/
public function close();
/**
* Method used to read from a session.
*
* @param mixed $id The key of the value to read
* @return mixed The value of the key or false if it does not exist
*/
public function read($id);
/**
* Helper function called on write for sessions.
*
* @param integer $id ID that uniquely identifies session in database
* @param mixed $data The value of the data to be saved.
* @return boolean True for successful write, false otherwise.
*/
public function write($id, $data);
/**
* Method called on the destruction of a session.
*
* @param integer $id ID that uniquely identifies session in database
* @return boolean True for successful delete, false otherwise.
*/
public function destroy($id);
/**
* Run the Garbage collection on the session storage. This method should vacuum all
* expired or dead sessions.
*
* @param integer $expires Timestamp (defaults to current time)
* @return boolean Success
*/
public function gc($expires = null);
}
// Initialize the session
CakeSession::init();